[Collins] 30L-1 Repair

[Dr. Gerald N. Johnson]

On 7/5/2014 9:57 AM, Glen Zook wrote:
> The 20.5-foot long input cable was eliminated for the 30L-1 being
> replaced with the normal 48-inch long RG58/U cable. The 20.5-foot long
> input cable is still recommended for the 30S-1.
>
> Supposedly, Art Collins told Warren Bruene to "fix" the problem and go
> back to the standard 48-inch long RG58/U input cable. However, I cannot
> absolutely verify that Art actually said this. I was still in high
> school when things were being "worked out" on the 30L-1. I only met Art
> Collins a few times during the period I was employed by the Collins
> Radio Company here at the "new" corporate headquarters in Richardson,
> Texas. I did get to know Art somewhat better after I left the company in
> 1969 and Art sold out to Rockwell International. Frankly, I never even
> considered asking him about the 30L-1 input.

Art did stick his fingers into every project even when he wasn't 
competent to change the engineering designs. His knowledge of circuit 
fundamentals was minimal and sometimes flawed. One time I was working on 
coils for a working paper he had commissioned and was measuring the Q of 
a large coil (wound of 1-1/2" copper water pipe, way too big to connect 
to a Q meter) by measuring the 3 dB bandwidth. He came to see the work 
being done and saw me using an abacus to compute delta F and wondered 
why I couldn't do that on a slide rule. I was working at low signal 
levels and didn't want the RF noise of a Friden and pocket calculators 
weren't even a dream in 1965. He slowed the project by getting computer 
programmers involved, but I still had to compute the Q by hand to see 
where my next frequency was going to be when working around suckouts of 
the tuned coil caused by the unloaded end of the tapped coil. Once the 
programmers learned that I didn't do an orderly progression of frequency 
that I sometimes moved back so they had to sort the frequencies, their 
plots were very nice and made the final report fancier than hand plots. 
But how does one compute the small differences between large numbers on 
a slide rule? Art couldn't show me and I offered him my fancy Loglog 
duplex Vector slide rule for the task.

I'm nost sure Warren had much to to with the 30L-1. It began as a home 
project of a couple engineers and was adopted and probably adapted after 
they proved it to work at home.

When I was there, '63 to '66, Warren was in a consulting roll, not hands 
on design in the projects I worked on. He didn't visit we junior 
engineers who were doing much design work.
>
> Of course, the 30L-1 linear is different from the original 30L-1
> transmitter. The 30L-1 transmitter had several prototype units built and
> the transmitter was advertised in several places as the 30L-1 before Art
> changed the nomenclature to KWS-1.

There were no 30L-1 SSB transmitters shipped as far as I know.

Because the sequential serial numbers of the 75A-4 affected its sale 
price and value even at dealers because of circuit changes, Are decreed 
that the S-line serial numbers must be issued in random order. which 
certainly doesn't help trace what the circuits should be but he also let 
the art department talk him into changes in style from winged emblem to 
meat ball and the S-line crew designed new versions with new features so 
those two negated the randomness of serial numbers. And then the initial 
purchase of random serial number tags wasn't enough to cover the entire 
production run so a new set with later serial numbers had to be 
acquired. Not a great idea that was wrecked by other ideas, not the sign 
of global thinking.

It would have been better for the 75A-4 to have recalled the early 
versions and to have updated them to the later circuitry that performed 
better, then they serial number bias would have been eliminated.
>
> Glen, K9STH
> Technical Adviser CCA
>
> website: http://k9sth.com
>
73, Jerry, K0CQ, Technical Adviser to the Collins Radio Association